Temperature-dependent quasiparticle band structure of an antiferromagnetic two-layer EuTe film

The temperature-dependent quasiparticle band structure of an antiferromagnetic two layer EuTe film is calculated using the s-f model. The one electron part required for the many body evaluation was obtained from TB-LMTO band structure calculation. A suitable supercell with five layers of empty spheres was used in the band structure calculation to obtain the Bloch energies of the film. The quasiparticle band structure of the (10 0) film is calculated at different temperatures and we find significant correlation effects in the spectrum. Some bands exhibit wave-vector-dependent splitting and the magnitude of the split-gap increases with increasing temperature. It is clearly seen as the combined effects of correlation and temperature. We find a red-shift of the conduction band edge of this EuTe film with respect to temperature whereas the bulk EuTe exhibits blue shift. (C) 2003 Elsevier B.V. All rights reserved.